Aspects of the animal fat use at the diesel engine fuelling

The general objective of the research is analyzes of the preheated gas oil-animal fat blends use at the experimental diesel engine, type CFR- IT9-3M, adequate instrumentation. The engine was fuelled firstly with diesel fuel then with different diesel fuel-animal fats blends (5%, 10%, 15% animal fats content in mixture with diesel fuel). The main animal fat advantages - cetane number and calorific value close to diesel fuel, higher oxygen content it recommend a good alternative fuel for diesel engines. But, the high viscosity and poor vaporization characteristics of animal fats need prior their heating. The results of experimental investigations show the animal fats effects on auto ignition delay, on the combustion parameters and on the pollutants emissions level. Thus, at the animal fats content increase in mixture with diesel fuel, for same engine adjustments, were obtained the follow results: auto ignition delay increases with ~20%; maximum gas pressure decreases with 10%; gas temperature decreases with 8%; indicate efficiency decreases with 10%; NOx emissions level decreases with 30%; CO emission level increases with 28%; HC emissions level increases with 58%; CO2 emission level decreases with 3.5% and smoke emissions decreases with 65%. Was established the animal fats effects on the fuel auto ignition and combustion. Animal fats can be considered a good alternative fuel for diesel engine, assuring the replace of the fossil fuels and resolving the major problem of animal wastes.